• Title/Summary/Keyword: SSFPI

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SSFP Interferometry (SSFPI) Technique Applied to functional MRI - A Fast and Direct Measurement of Magnetic Susceptibility Effect (SSFPI 기법을 이용한 MR 뇌기능 영상 -고 속의 자화율 효과의 직접적인 측정)

  • 정준영
    • Journal of Biomedical Engineering Research
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    • v.17 no.4
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    • pp.525-534
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    • 1996
  • We have developed a fast steady state free precession interferometry (SSFPI) technique which is useful for the fMRl (functional Magnetic Resonance Imaging). As is known, SSFP sequence with a suitable adjustment of Vadient (readeut) allows us to measure precession angle 6 which in tw relates to the field inhomogeneity. Combining the two pulses (known as FID and Echo) in FADE (Fast Acquisition Double Echo) sequence, for example, one can obtain the interference term which is directly related to the precession angle It has been known that a fast high resolution magnetic field mapping is possible by use of the modified FADE sequence or SSFPI, and we have attempted to use the SSFPI technique for the susceptibility-induced fMRl. When the method is applied to the susceptibility effect based functional magnetic resonance imaging (fMRl), it was found that the direct susceptibility effect measurement was possible without perturbations such as the backgrounds and inflow effect. In this paper, simulation results and experimental results obtained with 2.0 Tesla MRI system are presented.

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Observation of Susceptibility Change in fMRI Using SSFP Interferometry (SSFPI) Technique (핵자기 뇌기능 영상에서 SSFPI 기법을 이용한 자화율효과의 관찰)

  • Chung, J.Y.;Chung, S.C.;Ro, Y.M.;Cho, Z.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.11
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    • pp.173-176
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    • 1995
  • We have developed a fast steady state free precession interferometry (SSFPI) technique which is useful for the fMRI (functional Magnetic Resonance Imaging). As is known, SSFP sequence with a suitable adjustment of gradient (readout) allows us to measure precession angle $\theta$ which is in turn related to the field inhomogeneity [1-3]. When the method is applied to the susceptibility effect based functional magnetic resonance imaging (fMRI), it was found that the direct susceptibility effect measurement was possible without perturbations such as the backgrounds and inflow effect. In this paper, simulation results and experimental results obtained with 2.0 Tesla MRI system are also presented.

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